class  类人猿 {

   void crySpeak(String s) {

       System.out.println(s); 

   }  

}

class People extends 类人猿 {

   void computer(int a,int b) { 

      int c=a*b;

      System.out.println(c); 

   }

   void crySpeak(String s) {

      System.out.println("***"+s+"***"); 

   }  

}

public class Example5_10 {

   public static void main(String args[]) {

      类人猿 monkey;

      People geng = new People();   

      monkey = geng ; //monkey是People对象geng的上转型对象

      monkey.crySpeak("I love this game");//等同于geng.crySpeak("I love this game");

      People people=(People)monkey; //把上转型对象强制转化为子类的对象

      people.computer(10,10);

   }

}
